1. Field of the Invention
The subject invention relates generally to tools for machining complex part configurations, and more particularly, to a ball-end milling cutter tool for multi-axis milling or super abrasive machining of complex surfaces such as airfoils for gas turbine rotor blades and vanes.
2. Description of Related Art
In aerospace manufacturing, it is customary to use a ball-end milling tools to produce machined surfaces. The tapered ball-end milling tool has been the standard in the industry, since it offers flexibility on the range of axial step-over which the milling tool can achieve during stripe milling processes on most machine parts.
However, this standard tool design often limits the step-over range for some surface designs such as twisted airfoils or other complex surfaces present on gas turbine rotor blades and vanes. This results in lower material removal rates, longer cycle times, lower productivity and higher machining costs. In addition, the standard ball-end milling tool can cause rubbing or gouging when machining large airfoils with a relatively severe twist, such as those employed in the compressor section of the Pratt & Whitney PW1000G Geared Turbofan (GTF) engine.
It would be beneficial therefore, to provide a ball-end milling tool configured in such a manner so as to provide greater step-over range on airfoil surfaces with relatively severe twist, and to reduce or otherwise eliminate the rubbing and gouging problems associated with using a standard ball-end milling tool to machine such highly complex surfaces.